9.9hp Evinrude Lower Unit Removal

I have a 1982 9.9hp Evinrude long shaft I am having a hard time removing the lower unit on. I removed the 6 bolts attaching leg extension to the exhaust housing but cant get the LU to drop down enough to get anything on the shift rod screw. Leroy says to use a rubber mallet to separate it enough to get the shift rod screw off then finish separating it by driving wooden wedges in between. This seems reasonable but wanted to see if anyone had any additional tips? The motor has some corrosion on the LU, exhaust leg, and bottom cowl but the 6 LU bolts came out easy so I was hoping the drive shaft wasn't stuck either. I ran out of daylight tonight so won't get back to it until tomorrow evening or this weekend.

Pappy said:

By moving the shift lever on the side of the engine you will be able to separate the gearcase better.
You may have to gently separate the brass shift rod retainer prior to re-inserting the shift rod.
Use grease on every screw plus the splines on the driveshaft. Teflon grease if used in salt water.

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Thanks pappy. I have the shift lever set to the forward position but haven't tried shifting it back and forth to see if that will help dislodge it. I does feel like the driveshaft is free and that the shift rod connection is what is holding me up though. I'll give it another try today after work.

really its not going to dislodge it because its probably not even stuck

try putting it in reverse. This should drop the linkage down and this and this will give you additional room to get at the linkage connector.

WMK - did you find the issue ?
I remember my first time trying to drop the foot.
I had no idea there was a brass coupling holding
the upper and lower shift rods together. ](*,)
What Pappy and Perch said, remove the oval side
inspection plate and you can see the connector.
it takes a 7/16" socket (in most cases) and the
bolt must be removed completely - not just loosened.
as it sits in a groove holding the two rods in place.






.

ugh my 1959 40 hp Johnson had that setup

it can be a pain in the butt lol

trying to work on it through that little window

brings back memories

I got it tonight. I had to use a socket though as a flathead wasn't cutting it. My new problem is that the driveshaft is seized up in the crank. I turned it upside down and sprayed a ton of PB Blaster down the shaft to let it soak for a day or two.

Driveshaft is still seized solid into the crank. I guess I am going to have to find a better penetrating product. Auto trans fluid seems to be a popular option from what I have read other places online? What do you guys say? I plan on soaking it another couple of days and then tapping it into the crank to see if it will help it seep down a little deeper. Then try to get it out a few more days of soaking.

This has been a pretty unfortunate speedbump. Despite corrosion on the lower unit and inside the leg, the exterior of the powerhead is really clean and it runs like a top in a barrel. I was hoping a simple swap from longshaft to short was all it would take before I could drop it on my boat and be out fishing.

Also, with regards to the visible corrosion, is there a proven method to chemically flush a salt motor in a barrel with specific additives to help break down anything withing the powerhead cooling system?

Thanks Pappy. I am confused about something though...when you are talking about wedging the powerhead on one side and turning the crank, should the LU be put back on and tightened down? Thus creating a moment on the spline interface of the crank/driveshaft to help break it free as it is turned?

wmk0002 said:

Driveshaft is still seized solid into the crank. I guess I am going to have to find a better penetrating product.

Click to expand...

Lookie ... we have a post here with the BEST PENETRATING FLUID ever ... and you can make it yourself simply!

https://forum.tinboats.net/viewtopic.php?f=4&t=39672

DaleH said:

wmk0002 said:

Driveshaft is still seized solid into the crank. I guess I am going to have to find a better penetrating product.

Click to expand...

Lookie ... we have a post here with the BEST PENETRATING FLUID ever ... and you can make it yourself simply!

https://forum.tinboats.net/viewtopic.php?f=4&t=39672

Click to expand...

Thanks! I had seen that recommended elsewhere but those tests performed really seem sell it. I'll give it a try.

Pappy said:

Sorry!!! I missed the fact that the gearcase was now off. Never mind the wedging.
Okay....you can try your penetrating fluid until it either comes loose or you get bored.
In the meantime start loosening your powerhead fasteners. Am pretty sure you will have to anyway.
We will go from there.........

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Ah, thanks. I'll do that and update in a few days on how the penetrating fluid is working.

Got the driveshaft out last night. Never used anything other than PB Blaster but wished I had tried the acteone/ATF mix mentioned. Cleaned up the gouges in the driveshaft from the vice grips and cleaned the driveshaft's upper splines and upper portion of the shaft with with a wire wheel. There is some pitting but the driveshaft looks pretty decent overall. The motor is still upside down and crank still holding leftover PB Blaster. Gonna let it soak another day or two and try to clean it out with a gun cleaning kit. When I reinstall the shortshaft driveshaft LU I will grease it heavily to keep it from seizing again. I'm going to pull the powerhead at some point and put on a 15 hp exhaust tube so I will clean it more appropriately at that point in time.

Since this outboard had corrosion all the way up the driveshaft, and visually on the exterior of the LU and exhaust leg, would it be wise to flush the motor in a barrel with some sort of chemical to help flush the cooling passages? The motor ran great at slow speed in a barrel before I tried the short shaft conversion and water was pumping good out of the exhaust port on upper part of the leg, so it seems ok. Would the real test to be to simply run it at WOT and check for any signs of overheating or hotspots caused by blockage?

I dont know if I would be running anything through it, it might cause more harm than good

does it have a thermostat housing or other opening to the cooling system that you could look in to inspect for corrosion?

I know some motors you can take the exhaust cover off the side of the motor and it would expose the cooling passages, might be worth doing

if it were my motor I would probably just run it and monitor it carefully for a while until you have confidence that its ok

perchjerker said:

I dont know if I would be running anything through it, it might cause more harm than good

does it have a thermostat housing or other opening to the cooling system that you could look in to inspect for corrosion?

I know some motors you can take the exhaust cover off the side of the motor and it would expose the cooling passages, might be worth doing

if it were my motor I would probably just run it and monitor it carefully for a while until you have confidence that its ok

Click to expand...

Thanks. I began to think after my last post that it may cause more harm than good. It cooled fine running in a barrel so I'm sure it is ok for now. I will just closely monitor the engine temp the first few hours I use it on the water.